Chichijima (父島) is the largest and most populous island in the Bonin or Ogasawara Islands. Chichijima is about 240 km (150 mi) north of Iwo Jima. 23.5 km2 (9.1 sq mi) in size, the island is home to about 2,120 people (2021). Connected to the mainland only by a day-long ferry that runs a few times a month, the island is nonetheless organized administratively as the seat of Ogasawara Village in the coterminous Ogasawara Subprefecture of the Tokyo Metropolitan Government. Together with the Volcano and Izu Islands, it makes up Japan's Nanpō Islands.

The Bonin Islands, also known as the Ogasawara Islands (小笠原諸島), is a Japanese archipelago of over 30 subtropical and tropical islands located around 1,000 kilometers (620 mi) SSE of Tokyo and 1,600 kilometers (1,000 mi) northwest of Guam. The group as a whole has a total area of 84 square kilometers (32 sq mi) but only two of the islands are permanently inhabited, Chichijima and Hahajima. Together, their population was 2,560 as of 2021. Administratively, Tokyo's Ogasawara Subprefecture also includes the settlements on the Volcano Islands and the Self-Defense Force post on Iwo Jima. The seat of government is Chichijima.